Abstract: The present invention relates to binary methods and compositions comprising hypohalite (preferably hypochlorite) and peroxide (preferably hydrogen peroxide) directed to the killing of pathogenic microbes such as parasites, bacteria, fungi, yeast, and prions, the oxidation of toxins, and the preparation of potable water. The binary methods and compositions extend the microbicidal potency of conventional hypochlorite by providing additional singlet molecular oxygen generated in situ, and offer more control over reactive chlorination exposure than hypochlorite alone. This combination is a highly effective disinfecting and decontaminating agent, capable of disinfection, detoxification, or deactivation of biological contamination and many chemical toxins, facilitating the sterilizing of surfaces and solutions, and the production of potable water.